If it’s a short tour you will generally need to pay for you optionals on day 1 or 2. You can use cash (Euro’s) or credit card to pay for them (I’d go for the CC, much safer than lugging around all that money).

If you’re on a longer tour then sometimes you will book and pay for optionals in two parts; the first lot on day 1-2 and the second part about half-way through.

As cdm115 mentioned, TM will expect payment for all the optionals within the first few days. If it’s a long tour, there will probably be 2 installments – half at the start and the balance midway thru the tour. Do not hand over large payments on the street for obvious reasons – preferably within the safety confines of the coach.

On my European tour last year, you had to pay in cash, Euros. He gave us a few days to pay, the only thing was the lake cruise in Lucerne we had to pay for that day. The other optionals, we had a while to pay for, I think about 5 days. And he would only accept money while we were on the coach. This was a longish tour, Road to Athens.

Generally you pay for the optionals in euros or the local currency. The TM’s know that people often don’t have enough cash the first day and will give you a few days to get the cash. You wont be the only one who didn’t bring that much in euros the first day. You can exchange money on the ferry to France and can get them from ATM’s at the rest stops.